Family: Papilionidae, Swallowtails view all from this family
Description 3 1/8-5 1/2" (79-140 mm). Males and some females above and below are yellow with black tiger-stripes across wings and black borders spotted with yellow. Long, black tail on each HW. HW above and below usually has row of blue patches inside margin, with orange spot above and sometimes much orange below, running through yellow. Dark form females are black above with border-spotting of yellow, blue, and orange (blue sometimes becomes cloud on HW), below brown-black with shadowy "tiger" pattern. Yellow spots along outer edge of FW below are separate in all but northernmost populations. Most have orange uppermost spot on outer margin of HW above and below and orange spot on trailing edge.
Similar Species Western Tiger Swallowtail has spots on outer margin of lower FW that run together into band; uppermost spot on border of HW is yellow; blue spots are more violet-tinted. Spicebush Swallowtail is distinguished from dark female Tigers by bluish-green spotting around margins above and orange spot on costa of HW (not outer border).
Life Cycle Yellow-green, globular egg, 1/32" h x 3/64" w (0.8 x 1.2 mm), very large for a butterfly. Young caterpillar brown and white, resembling bird droppings; mature caterpillar, to 2" (51 mm), is green, swollen in front, with big, false, orange and black eyespots and band between 3rd and 4th segments. Mottled green or brown sticklike chrysalis, to 1 1/4" (32 mm), overwinters. Great variety of host plants, mostly broadleaf trees and shrubs; favorites include willows and cottonwoods (Salicaceae), birches (Betulaceae), ashes (Fraxinus), many cherries (Prunus), and tulip-poplars (Liriodendron tulipifera).
Flight 1-3 broods; spring-autumn, actual dates vary with latitude.
Habitat Broadleaf woodland glades, gardens, parks, orchards, and roads and rivers.
Range Central Alaska and Canada to Atlantic; eastern United States south to Gulf coast and southern Texas. Rarer at northern and southern edges of range.
Discussion This species is the most widely distributed tiger swallowtail, and one of the most common and conspicuous butterflies of the East. Alaskan, Canadian, and northeastern butterflies are smaller and paler than those of the eastern states. Feeding in groups, adults take nectar from a wide range of flowers. The black female form has evolved to mimic the distasteful Pipevine Swallowtail; its presence in the population reflects the abundance of the species it mimics.
